We fixed the most annoying slam-bang-rattle on our Trop-i-cal which was the entire dash jumping up and down. Looking in through the thin drawer slot in the middle, we found a wooden wedge had fallen out. We replaced it with two thinner wedges which we glued in place after tapping them together to tighten them. I would like to stiffen the dash even further by installing a brace on the right sidewall under the dash.
Other than that, I just staggered around the coach while the DW was driving it on rough roads and tried to identify sources of noise. New weatherstripping on the screen door helped as did some stick-on felt pads on the fold-away table behind the passenger seat.
When we hit the road, all our dishtowels and throw pillows get stowed in the dish & glasses cabinets as well as the wine locker. That really quiets them down. Nothing is more scary than forgetting to lack the pots & pans drawers shut and having them slam open on the first left turn, spilling frying pans out across the floor.
Visors can be another annoying source of noise. Ours were constantly banging against the bottom of the overhead cabinets. The coach still sounds like the change box on a transit bus when we get in the right lane where the truckers have washboarded the blacktop, but on a decent road it's almost comfortably quiet.